Nebulizer and method for producing a nebulizer

ABSTRACT

The invention relates to a nebulizer comprising an aerosol generator, a nebulizing chamber and an outlet, the aerosol generator being designed to release an aerosol into the nebulizing chamber and the outlet being designed to allow the removal of the aerosol from the nebulizing chamber. To achieve a high output rate, a wetting surface is provided in the nebulizing chamber.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/328,989 filed Jan. 25, 2017, which is a National Stage application ofPCT/EP2015/060454, filed May 12, 2015, which claims priority to GermanPatent Application No. 10 2014 215 064.7, filed Jul. 31, 2014, which arehereby incorporated by reference in their entirety.

The invention relates to a nebulizer comprising an aerosol generator aswell as to a method for producing a nebulizer.

Known from DE 19602628 A1 are nebulizers comprising a nozzle arranged ina nebulizing chamber and an air inlet pipe protruding into thenebulizing chamber.

The object of the invention is to provide a nebulizer with which a highoutput rate can be achieved as well as a method for producing such anebulizer. This object is solved by a nebulizer having the features ofclaim 1 and by a method having the features of claim 11.

According to one embodiment, the object is also solved by a nebulizercomprising an aerosol generator, a nebulizing chamber and an outlet,wherein the aerosol generator is configured to release an aerosol intothe nebulizing chamber, the outlet is configured to allow removal of theaerosol from the nebulizing chamber, and a wetting surface is providedin the nebulizing chamber, the wetting surface being provided on aplastic component.

Output rate is to be understood as the amount of aerosol that passesthrough the outlet over time.

An aerosol is a mixture of particles suspended in a gas. The suspendedparticles can be solid or liquid. Both solid and liquid suspendedparticles may also be present. Aerosol droplets are liquid droplets in agas.

A nebulizer is a device that is configured to provide and release anaerosol.

An aerosol generator is a device that is configured to generate anaerosol. An aerosol generator is preferably a device that is configuredto generate liquid droplets and to mix these with a gas. An aerosolgenerator preferably comprises a nebulizer, an atomizer, a humidifier, acompressed air nebulizer, an air atomizer, an electronic nebulizer, anultrasonic nebulizer, an electrohydrodynamic nebulizer, an electrostaticnebulizer, a membrane nebulizer, a nebulizer having a vibratingmembrane, an electronic nebulizer having a vibrating membrane, a meshnebulizer, a nozzle nebulizer, an inhaler (MDI), a powder atomizer (DPI)or a combination thereof. In one embodiment, the inhaler comprises apressurized canister comprising a medicament and a propellant. Thecanister is expediently connected to an actuator that can be operated byhand. It is advantageous for the inhaler to be configured so as torelease a specific amount of medicament in aerosol form upon activation.In one embodiment, the aerosol generating device is configured for usewith ventilators.

A nebulizing chamber is a space that is configured such that aerosol canflow therethrough. A nebulizing chamber can be a space that isconfigured to accommodate, at least temporarily, an aerosol.

An outlet is a device that is provided to allow an aerosol out of thenebulizing chamber. The outlet is expediently configured to be connectedto a component such as a mouthpiece or a mask.

A plastic component is a component comprising a plastic. The componentcan be made entirely of plastic. The plastic can be an organic,polymeric solid, which has been produced synthetically orsemi-synthetically from monomeric organic molecules or biopolymers. Theplastic can be a thermoplastic, a thermoset or an elastomer. The plasticcomponent can comprise, for example, a polypropylene.

A wetting surface is a surface that is configured to be wetted by aliquid. Wetting takes place when a liquid forms a contact angle of 90degrees or less with the wetting surface.

In one embodiment, the wetting surface has, at least temporarily,preferably permanently, a surface tension of 32 to 5000 millinewtons permeter (mN/m). The surface tension is preferably between 35 and 400millinewtons per meter (mN/m), particularly preferred between 44 and 73millinewtons per meter (mN/m). The surface tension can be between 50 and72 millinewtons per meter (mN/m).

The wetting surface can comprise a wetting material. Preferred wettingmaterials are metals and glass. In one embodiment, the wetting surfacecomprises ABS.

The wetting surface can have a predetermined surface roughness. Theaverage roughness value R_(a) can be between 6.3 and 0.006. The averageroughness value R_(a) is preferably between 1.6 and 0.01, particularlypreferred between 0.5 and 0.006. The surface roughness is preferablyprovided by a correspondingly configured mold, such as an injection moldor a die casting mold, and a corresponding production process.

The wetting surface can be cleaned.

The wetting surface can have a temperature of between 20 and 80 degrees,preferably between 40 and 50 degrees.

The wetting surface can have a surface treatment.

The wetting surface is preferably printed or coated, and it isparticularly preferred for it to be lacquered or laminated.

The wetting surface can be blasted. It can be blasted in particular withsand, glass beads, ceramics, steel, dry ice, corundum, steel grit, steelballs, cut wire, emery, bronze grit, blast furnace slag, calciumcarbonate granules or plastics.

The wetting surface can be corona treated, flame treated, fluorinated,plasma treated, in particular oxygen plasma treated or low-pressureplasma treated, ozone treated or UV light treated. It is particularlypreferred for the wetting surface to be a fluorinated wetting surface.The fluorinated wetting surface has preferably been obtained byreplacing hydrogen atoms of a polymer chain with fluorine atoms. Thefluorinated surface or fluorinated wetting surface has been exposed tofluorine, expediently a fluorine mixture. This preferably occurred atroom temperature, particularly preferred at 25° C. It is expedient if notemperature peaks thereby occurred. The depth of penetration of thefluorine atoms into the substrate is preferably in the molecular range.The properties of the base material have preferably remained unchanged.The base material comprises plastic, and the base material preferablycomprises ABS, EPDM, plastic from renewable resources, NBR, HNBR, PEEK,PMMA, polyamide, polyester, polyethylene, LDPE, UHMW-PE, POM, PET, EPDM,PBT, polycarbonate, polyphenyl sulfide, polysiloxane elastomer, polymercontaining glass fiber, copolymers, polypropylene, silicone, rubber orTPE. The surface energy of the wetting surface can have been adapted tothe surface energy of a liquid. The liquid preferably comprises salinesolution or a medicament.

In one embodiment, the fluorinated wetting surface has been obtained bygas phase fluorination. During gas phase fluorination, the object orcomponent is exposed to fluorine, expediently a fluorine mixture in gasform such that hydrogen atoms are replaced by fluorine atoms in theoutermost surface layer. A surface of a component can thereby be treatedrelatively independently of its geometry. The fluorinated wettingsurface has preferably been achieved by treating the component in avacuum reactor. The fluorinated component can have been treated as bulkmaterial in a preferably cylindrical chamber. It is advantageous for thefluorinated component to have been inserted into a preferably cubicchamber in a basket, a mesh box or a specific load carrier. Thefluorinated component can have been treated in a continuous flowreactor.

In one embodiment, the fluorinated wetting surface has been obtained byfurther processing fluorinated powder or granulate by means of injectionmolding or blow molding. The powder or granulate can thereby have beenfluorinated in such a manner that the fluorine atoms are located solelyin an outer area of the powder particles or granules. The fluorine atomscan also have penetrated deeper into the powder particles or granules orcan be located in all areas of the powder particles or granules. Thepowder or granulate has been expediently fluorinated using gas phasefluorination. Polyolefin powder or granulate has preferably been usedfor this purpose. The fluorination of the powder or granulate haspreferably occurred in a rotating drum having scoop components or in areactor having a movable stirrer. It is expedient for the reactor to becylindrical and for the stirrer to be configured such that it rotates.

A surface with a highly polar nature that is active over a long periodof time can thereby have been achieved without influencing the basematerial. The fluorination of the surface is preferably not reversible.A barrier layer, preferably a permeation layer, can have been formed.Permeation, diffusion, migration, friction, adhesion and adhesivenesscan have been reduced. Adherence, film formation, adhesion andwettability can have been increased. An improved drainage of liquids,quicker drying, a higher print quality, improved cleanliness owing tothe fact there is no adherence of dirt particles, as well as reducedcalcification and mold formation, improved assemblability or anoptically more attractive surface can have been achieved. Owing to thebarrier layer, it can be prevented that components of plastic materialdiffuse out of the surface or that the filling of a container penetratesa wall. Unpleasant odors, environmental burdens, swelling, a greasysurface and the peeling off of labels can be prevented. The achievedproperty can have long-term stability even after cleaning andsterilization processes. A surface of a workpiece can be fluorinatedsuch that the dimensions of the workpiece are the same before and afterfluorination. An antibacterial or antimicrobial effect can have beenachieved. The antibacterial or antimicrobial effect can be temporary.

The wetting surface can have been subjected to surface activation.

By providing the wetting surface, it can be achieved that liquiddroplets that reach a surface of the nebulizing chamber gather on thewetting surface. A liquid film can be formed. It is also possible toachieve the effect that liquid slides off of the surface.

This is advantageous since, on surfaces that are not wettable or areonly poorly wettable, liquid droplets can form which protrude a long wayfrom the surface. As a result hereof, a flow-throughable cross-sectionof the nebulizing chamber can be reduced. A reduced cross-section canresult in more aerosol droplets impinging upon and adhering to thesurfaces of the nebulizing chamber and the liquid droplets alreadypresent on the surface. These aerosol droplets are then unable to arriveat the outlet.

Furthermore, large droplets can detach from a poorly wettable surfaceand can drop down through a space through which an aerosol is flowing.Aerosol droplets are entrained therewith, which are then no longer ableto arrive at the outlet. As a result, the output rate is reduced.

In one embodiment, a wetting surface is provided such that a liquid filmcan form thereon and that droplets which collide with the liquid filmcan produce further droplets.

In one configuration, the respirable rate can be increased by up to 30%.For this purpose, a surface treatment is preferably provided on a nozzleattachment and a lower part of the nebulizer. In preferredconfigurations, the duration of therapy can be reduced by 20%, theresidual volume can be reduced, the patient can receive a higher dose ofmedicament in a shorter time and the efficiency of the nebulizer can beincreased. These properties preferably remain even after cleaning in adishwasher and after 10 autoclave cycles at 134° C.

In one embodiment, the aerosol generator comprises a nozzle. In thecombination with a nozzle it is particularly expedient to provide awetting surface since nozzles can generate aerosols with particles thathave large differences in diameter. As a result, it is rather very largeliquid droplets which adhere to surfaces of a nebulizing chamber. Thesecan greatly reduce a cross-section though which a flow is to pass andcan greatly reduce the output rate.

The nozzle is preferably provided with a liquid supply and configuredsuch that gas can flow therethrough. The nozzle can be configured as atwo-substance nozzle with internal mixing or as a two-substance nozzlewith external mixing.

It is expedient for the nebulizing chamber to comprise an aerosol guidethat connects the aerosol generator to the outlet, and for the aerosolguide to comprise the wetting surface. A large part of the aerosol thatis suitable for being guided to the outlet can thus arrive at theoutlet.

The aerosol guide is preferably a hollow space, through which thegenerated aerosol must pass to arrive at the outlet. The aerosol guideexpediently comprises a continuous path, along which the aerosol canpass through the aerosol guide.

The aerosol guide can be partially provided with the wetting surface andis preferably entirely coated with the wetting surface.

In one embodiment, a surface of the aerosol guide comprises the wettingsurface. Since surfaces are easy to process, a cross-section of theaerosol guide can thus be at least largely maintained in a simplemanner.

A surface is preferably a two-dimensional boundary surface of a body. Asurface can be flat, a surface can also be curved.

If an edge of the aerosol guide has the wetting surface, it can beachieved that liquid gathers particularly well at the edge. The wettingsurface is preferably configured such that liquid flows away well fromthe edge. The effect that liquid accumulates at the edge in such amanner that the edge is shifted can be reduced or prevented.

This is particularly desirable in the case of edges that have afunction. The function may be to provide a defined cross-section, suchas in the case of an aperture. A function may also be to provide adefined path for filtering out undesirable components in the aerosol.The edge can thereby delimit a filter area, as described below, which isprovided to filter out aerosol droplets having a predetermined diameterfrom an aerosol flow.

In one embodiment, the aerosol guide comprises a passage and the passagehas the wetting surface. As a result hereof, it can be achieved that thecross-section of the aerosol guide is largely or completely maintainedat a position that is particularly important for the output rate.

A passage is preferably an area in the aerosol guide that has a smallercross-section than adjacent areas. A passage can be a narrowing, whichis configured to influence pressures or speeds of fluids flowingtherethrough, such as a nozzle or an aperture.

It is advantageous for the nebulizing chamber to have a delimiting wallcomprising the wetting surface. It can hereby be achieved thatcomparatively large amounts of liquid are quickly guided back into areservoir. Furthermore, the residual amount that remains in thenebulizer after use and is not made available to the patient can bereduced particularly well in such a manner.

A delimiting wall is a wall which delimits the nebulizing chamber fromits surroundings.

The nebulizing chamber can comprise an air supply which has the wettingsurface. The supplied air can thus be guided in a particularly precisemanner.

An air supply is configured such that it can allow ambient air into thenebulizing chamber. In one embodiment, the air supply is configured toconduct ambient air past the aerosol generator to the outlet. Theaerosol can thereby be effectively guided to the outlet.

The air supply is preferably configured as an air inlet pipe.

In one embodiment, the nebulizing chamber comprises a baffle surface andthe baffle surface comprises the wetting surface. It can be achieved inthis manner that aerosol droplets applied to the baffle surfaceinfluence the surface and contour of the baffle surface to the smallestpossible extent. A constant function of the baffle surface can beachieved.

A baffle surface is a surface that is configured such that aerosol movesagainst it. Upon contacting the baffle surface, aerosol droplets canbreak up into smaller aerosol droplets.

A baffle surface can be provided on an airflow control. The airflowcontrol can be provided at the outlet of a fluid stream. In oneembodiment, the airflow control is arranged in the fluid stream oppositea discharge opening. The discharge opening is expediently the dischargeopening of a nozzle, preferably a gas nozzle.

A baffle surface can be provided on a baffle. A baffle is a componentthat is arranged adjacent to an aerosol generator.

The baffle is preferably arranged such that aerosol droplets having adiameter which is larger than a predetermined diameter can collidetherewith. For this purpose, it extends in one embodiment at least in aplane around the aerosol generator. It can be configured in particularin a cylindrical, frustoconical or conical manner.

The provision of a wetting surface on a baffle can be particularlyadvantageous if the aerosol guide is designed such that a particularlysmall flow-throughable cross-section is provided on the baffle. Adheringliquid could reduce this cross-section even further such that lessaerosol can flow to the outlet. By providing a wetting surface on thebaffle, it can be achieved that the liquid arriving at the baffle cangather on the baffle to a greater extent and remove itself more quicklyfrom the baffle.

In one embodiment, the nebulizing chamber comprises a filter area andthe filter area comprises the wetting surface.

So that it is able to fulfil the function of a filter, a filter area canbe arranged such that predominantly larger liquid droplets collidetherewith and smaller liquid droplets are guided past it. This can beachieved by arranging the filter area in a region that is designed suchthat an aerosol experiences a change in direction. In such regions,larger and smaller liquid droplets typically predominantly distributethemselves in certain sub-regions such that it can be determined via thearrangement and configuration of the baffle surface which liquiddroplets are filtered out.

The edge of the filter area can thereby determine which aerosol dropletsare still filtered out and which aerosol droplets can pass through thefilter area.

Owing to this function of the filter area, it is supplied with aparticularly large amount of liquid droplets. However, this functionalso requires a precise shape of the filter area. The shape of thefilter area can be changed in such a manner by liquid droplets disposedthereon that the droplet spectrum of the filtered-out liquid droplets isaltered.

The droplet spectrum characterizes the occurrence of liquid dropletswith certain diameters in the aerosol.

So as to keep the change to the shape of the filter area as minor aspossible, it is expedient to provide the filter area with a wettingsurface. As a result thereof, liquid droplets applied to the filter areacan gather on the filter area in such a manner that they barely changethe shape of the filter area. Furthermore, the wetting surface can beconfigured such that liquid droplets flow off thereof so well that theyare removed quickly from the filter area and little liquid is disposedon the filter area.

A filter area can be provided on a nebulizing chamber divider. Anebulizing chamber divider is preferably configured to divide thenebulizing chamber such that the aerosol has to undergo a change indirection in order to be able to arrive at the outlet. In conjunctionwith this function, the nebulizing chamber divider can, in accordancewith the principle described above, separate aerosol having a desireddroplet spectrum from aerosol having an undesired droplet spectrum.

The filter area can be provided on a labyrinth guide. A labyrinth guideis an aerosol guide which requires the aerosol to change direction atleast once, preferably at least twice or three times, when it is flownthrough. In conjunction with this property, the labyrinth guide can, inaccordance with the principle described above, separate aerosol having adesired droplet spectrum from aerosol having an undesired dropletspectrum.

The filter area can be provided on a baffle. The baffle is, as describedabove, preferably arranged such that a predetermined droplet spectrum isguided against it. For this purpose, it extends, as described above, inone embodiment at least in a plane around the aerosol generator. It canbe configured in particular in a cylindrical, frustoconical or conicalmanner. In order to be able to arrive at the outlet, the aerosol mustexpediently change direction in the region of the baffle, preferablyadjacent to a surface, in particular adjacent to an edge of the baffle.

The baffle is thereby expediently arranged such that, in accordance withthe principle described above, it prevents aerosol droplets that are notsupposed to arrive at the outlet from travelling along the path to theoutlet. Such aerosol droplets can be guided to a surface of the bafflesuch that they can collide therewith and adhere thereto. In oneembodiment, the nebulizer is configured such that inhaled air can flowinternally through the baffle past the aerosol generator, thereby takingaerosol with it, and continues to flow around the edge of the baffle andalong an outer side of the baffle in the opposite direction. Aerosoldroplets that are too large to follow this path are thereby deposited onthe inner side of the baffle. The positioning of the edge of the baffledetermines which aerosol droplets are still deposited on the baffle andwhich aerosol droplets are still able to continue further in thedirection of the outlet. It is therefore also important here for thedroplet spectrum of the aerosol to be guided to the outlet that theouter dimensions of the edge are not modified by adhering liquid sincethe filtered-out droplet spectrum can then change. As a result, it isparticularly expedient to provide a wetting surface on the edge of thebaffle, on the inner side of the baffle or on the entire baffle.

It is expedient for the nebulizing chamber to comprise a reservoir, forthe aerosol generator to be configured to cooperate with the reservoirand for the reservoir to comprise the wetting surface. Liquid canconsequently collect particularly well in a region of the reservoirintended therefor.

A reservoir is a storage means which is provided for storing liquids, inparticular for storing medicaments. The reservoir is expedientlyconfigured to release liquid to the aerosol generator. It isadvantageous for the nebulizer to be configured such that liquid thathas deposited on surfaces in the nebulizing chamber can reach thereservoir.

The object is furthermore solved by a method for producing a nebulizerhaving a wetting surface, which comprises the steps of: producing anebulizer comprising an aerosol generator, a nebulizing chamber and anoutlet, said aerosol generator being configured to release an aerosolinto the nebulizing chamber and said outlet being configured to allowremoval of the aerosol from the nebulizing chamber, and providing awetting surface in the nebulizing chamber, said wetting surface beingprovided by fluorination.

The invention will be described in more detail in the following by meansof embodiment examples and with reference to the enclosed drawings.

FIG. 1 shows an embodiment example of a nebulizer having a wettingsurface on an air inlet pipe.

FIG. 2 shows a cross-section of a nebulizer without a wetting surface.

FIG. 3 shows a cross-section of the nebulizer shown in FIG. 1.

FIG. 4 shows a nebulizer, in which the entire nebulizing chamber isprovided with the wetting surface.

FIG. 5 shows an embodiment example of a nebulizer having a wettingsurface on a baffle.

FIG. 6 shows a nebulizer comprising a nebulizing chamber, a mouthpieceand a membrane aerosol generator.

FIG. 1 shows an embodiment example of a nebulizer 1 having a wettingsurface 2 on an air inlet pipe 3. The nebulizer 1 shown in FIG. 1comprises a delimiting wall 4, which encloses a nebulizing chamber 5.Disposed in the nebulizing chamber 5 is an aerosol generator 6, which isconfigured as a two-substance nozzle 7. The two-substance nozzle 7comprises one gas channel 8 and three liquid channels 9, although onlytwo of the three liquid channels 9 are shown in FIG. 1. The gas channel8 has a connection for a compressed air source which is not shown. Theliquid channels 9 are configured to cooperate with a medicamentreservoir 10. The gas channel 8 and the liquid channels 9 adjacentlyopen out into an atomization region 11 of the two-substance nozzle 7.Provided opposite a mouth 12 of the gas channel 8 is an airflow control13.

An air inlet pipe 3 extends from an inlet opening 14 of the delimitingwall 4 in the direction of the two-substance nozzle 7. The outer side 15of the air inlet pipe 3 is provided with a wetting surface 2. Thewetting surface 2 extends over the entire length and half of thecircumference of the air inlet pipe 3. The wetting surface 2 therebyextends over that half of the circumference of the air inlet pipe 3which is facing an outlet 16 provided in the delimiting wall 4.

During operation of the nebulizer 1, a liquid medicament from themedicament reservoir 10 reaches the atomization region 11 through theliquid channels 9. Compressed air also reaches the atomization region 11through the gas channel 8. Upon inhaling, a patient sucks ambient airthrough the air inlet pipe 3 into the atomization region 11. An aerosolis produced in the atomization region 11 with the aid of the airflowcontrol 13. Upon inhaling, the patient sucks aerosol out of thenebulizer 1 through the outlet 16. As a result hereof, medicament liquidlands on the inner side of the delimiting wall 4 and on the air inletpipe 3. This medicament liquid reduces the size of the passage 18between the delimiting wall 4 and the air inlet pipe 3. As a result,less aerosol can reach the patient.

This effect is lower on the wetting surface 2, as will be described inthe following by means of FIGS. 2 and 3.

FIG. 2 shows a cross-section of a nebulizer 1 without a wetting surface.Fat liquid droplets 17 are disposed on the delimiting wall 4 and on theair inlet pipe 3. The passage 18 between the delimiting wall 4 and theair inlet pipe 3 is greatly reduced in size by the fat liquid droplets17. Many of the aerosol droplets that are guided through this passage 18from the atomization region 11 in the direction of the outlet 16 collidewith the fat liquid droplets 17 and cannot arrive at the outlet 16.

FIG. 3 shows a cross-section of the nebulizer 1 shown in FIG. 1. In thisnebulizer 1, fat liquid droplets 17 are also disposed on the delimitingwall 4 and on the air inlet pipe 3. However, no fat liquid droplets 17can be found in the region of the wetting surface 2, but rather flatliquid droplets 19. This is achieved owing to the good wettability ofthe wetting surface 2. Owing to the fact that there are no fat liquiddroplets 17 on the wetting surface 2, the cross-section of the passage18 is larger in this region. Fewer aerosol droplets collide with theflat liquid droplets 19. As a result, the output rate is greater than ina nebulizer 1 without a wetting surface 2.

FIG. 4 shows a nebulizer 1, in which the entire nebulizing chamber 5 hasbeen provided with the wetting surface 2. The inner wall of thedelimiting wall 4, the air inlet pipe 3, the inside of a connection 24,the two-substance nozzle 7 and the airflow control 13 are provided withthe wetting surface 2.

FIG. 5 shows an embodiment example of a nebulizer 1 having a wettingsurface 2 on a baffle 20. The nebulizer 1 shown in FIG. 5 essentiallycorresponds to the nebulizer 1 shown in FIG. 1. However, it isadditionally equipped with a baffle 20, a baffle section 21 and a guidesection 22.

The baffle 20 is arranged in the area of the atomization region 11. Itessentially has the form of a hollow cylinder and is arranged such thatthe atomization region 11 is disposed approximately in the middle of thelongitudinal axis of the baffle 20. The baffle 20 consequently extendsaround the atomization region 11. The baffle 20 is open at that end face23 which faces in the direction of the medicament reservoir 10. The endface 23 of the baffle 20 which is disposed closer to the outlet 16 iscovered by the baffle section 21.

The baffle section 21 extends up to the delimiting wall 4 in a regionadjacent to the outlet 16. A passage 18 is provided between the oppositeregion of the delimiting wall 4 and the baffle 20.

The guide section 22 extends from the baffle section 21 in the directionof the inlet opening 14. A passage 18 thereby remains between thedelimiting wall 4 with the inlet opening 14 and the guide section 22.The guide section 22 extends transversely between the outlet 16 and theregion of the delimiting wall 4 opposite thereto.

Upon operation of the nebulizer 1 shown in FIG. 5, an aerosol isgenerated according to the same principle as for the operation of thenebulizer 1 shown in FIG. 1.

Upon inhalation, the patient also sucks aerosol out of the nebulizer 1through the outlet 16. For this to happen, the aerosol must move fromthe atomization region 11 to the open end face 23 of the baffle 20. Theaerosol then has to change direction and pass through the passage 18between an outer side 15 of the baffle 20 and the delimiting wall 4.From the passage 18, it must flow in the direction of the inlet opening14 and then around the guide section 22 to the outlet 16.

This predetermined path serves to filter out undesired aerosol droplets.Aerosol droplets that are too large to follow the predetermined aerosolflow collide with the baffle 20 or the guide section 22. Only a smallregion for the aerosol to pass through is provided between the baffle 20and the two-substance nozzle 7. This region is restricted even furtherby the medicament depending on the level of liquid in the medicamentreservoir 10. The precise geometry of the baffle 20 determines thefiltered-out droplet spectrum. Owing to liquid disposed on the baffle20, both the size of the region for the aerosol to pass through isreduced and the geometry is changed. As a result hereof, more dropletsare filtered out such that the output rate is low. The filtered-outdroplet spectrum is also changed.

In order to minimize these effects, the entire baffle 20 is providedwith a wetting surface 2. In accordance with the principle described inFIG. 3, it is achieved owing to the provision of a wetting surface 2that flat liquid droplets 19 are formed, which cause little change tothe geometry of the baffle 20 and only slightly reduce the size of theregion for the aerosol to pass through.

With reference to FIGS. 1, 4 and 5, the invention has been described inconnection with a two-substance nozzle. However, it is not restricted tonebulizers having this type of aerosol generator.

FIG. 6 shows a nebulizer 1 comprising a nebulizing chamber 5, amouthpiece 25 and a membrane aerosol generator 26. The oscillatingmembrane 27 can be caused to oscillate, for example, by annular piezoelements that are not shown in the figure. During operation of thenebulizer 1, a liquid is disposed on one side of the oscillatingmembrane 27, at the top in FIG. 6, which is transported through openingsin the oscillating membrane 27 and is released on the other side of theoscillating membrane 27, at the bottom in FIG. 6, into the nebulizingchamber 5 as an aerosol.

The nebulizing chamber 5 is provided with a wetting surface 2.

The patient can inhale the aerosol disposed in the nebulizing chamber 5at the mouthpiece 25. So as not to cause the patient to put down thetherapy device after inhaling the aerosol, the mouthpiece 25 has anexhalation opening 28 which is sealed by a flexible valve element 29. Ifthe patient exhales into the mouthpiece 25 and thus into the nebulizingchamber 5, the flexible valve element 29 opens such that the exhaled aircan exit the interior of the nebulizer 1. Upon inhalation, ambient airflows through the membrane aerosol generator 26.

LIST OF REFERENCE NUMBERS

1 Nebulizer

2 Wetting surface

3 Air inlet pipe

4 Delimiting wall

5 Nebulizing chamber

6 Aerosol generator

7 Two-substance nozzle

8 Gas channel

9 Liquid channels

10 Medicament reservoir

11 Atomization region

12 Mouth

13 Airflow control

14 Inlet opening

15 Outer side

16 Outlet

17 Fat liquid droplets

18 Passage

19 Flat liquid droplets

20 Baffle

21 Baffle section

22 Guide section

23 End face

24 Connection

25 Mouthpiece

26 Membrane aerosol generator

27 Oscillating membrane

28 Exhalation opening

29 Valve element

1. A nebulizer comprising an aerosol generator, a nebulizing chamber,and an outlet, wherein the aerosol generator is configured to release anaerosol into the nebulizing chamber and the outlet is configured toallow removal of the aerosol from the nebulizing chamber, wherein awetting surface is provided in the nebulizing chamber, said wettingsurface being provided on a plastic component, the wetting surface beingconfigured to be wetted by the aerosol comprising a water-based liquidsuch that the liquid forms a contact angle of 90 degrees or less withthe wetting surface, the nebulizing chamber further comprising a filterarea, and the filter area comprising the wetting surface, and/or thenebulizing chamber further comprising a baffle surface, and the bafflesurface comprising the wetting surface, and/or the nebulizing chamberfurther comprising a delimiting wall, and the delimiting wall comprisingthe wetting surface.
 2. The nebulizer according to claim 1, wherein theaerosol generator comprises a nozzle.
 3. The nebulizer according toclaim 1, wherein the nebulizing chamber comprises an aerosol guide,which connects the aerosol generator to the outlet, and the aerosolguide comprises the wetting surface.
 4. The nebulizer according to claim3, wherein a surface of the aerosol guide comprises the wetting surface.5. The nebulizer according to claim 3, wherein an edge of the aerosolguide comprises the wetting surface.
 6. The nebulizer according to claim1, wherein the aerosol guide comprises a passage and the passagecomprises the wetting surface. 7.-9. (canceled)
 10. The nebulizeraccording to claim 1, wherein the nebulizing chamber comprises areservoir, the aerosol generator is configured to cooperate with thereservoir, and the reservoir comprises the wetting surface.
 11. A methodfor producing a nebulizer having a wetting surface, which comprises thesteps of: producing a nebulizer comprising an aerosol generator, anebulizing chamber and an outlet, said aerosol generator beingconfigured to release an aerosol into the nebulizing chamber and saidoutlet being configured to allow removal of the aerosol from thenebulizing chamber; and providing a wetting surface in the nebulizingchamber, the wetting surface being configured to be wetted by theaerosol comprising a water-based liquid such that the liquid forms acontact angle of 90 degrees or less with the wetting surface, thenebulizing chamber further comprising a filter area, and the filter areacomprising the wetting surface, and/or the nebulizing chamber furthercomprising a baffle surface, and the baffle surface comprising thewetting surface, and/or the nebulizing chamber further comprising adelimiting wall, and the delimiting wall comprising the wetting surface.12. The nebulizer according to claim 1, wherein the wetting surface hasa surface tension between 35 and 400 millinewtons per meter.
 13. Thenebulizer according to claim 1, wherein the wetting surface has asurface tension between 44 and 73 millinewtons per meter.
 14. Thenebulizer according to claim 1, wherein the wetting surface has asurface tension between 50 and 72 millinewtons per meter.
 15. Thenebulizer according to claim 1, wherein the wetting surface has anaverage surface roughness value between 6.3 and 0.006.
 16. The nebulizeraccording to claim 1, wherein the wetting surface has an average surfaceroughness value between 1.6 and 0.01.
 17. The nebulizer according toclaim 1, wherein the wetting surface has an average surface roughnessvalue between 0.5 and 0.006.
 18. The nebulizer according to claim 1,wherein the wetting surface comprises a coating formed directly on theplastic component.
 19. The method according to claim 8, whereinproviding the wetting surface comprises forming a coating directly onthe plastic component.